2011 Rav 4 Parking sensor enable

[Nonsensor]

MiL has a Rav 4 2011 RHD assume UK spec. 

This has a reverse camera but she is adamant it had parking sensors (I see no bumper warts) that have recently stopped. 

I cannot find any switches, menu items or other way in which they could be enabled / diabled. All vids and info online seems gen 4 or 5. 

Is there a way these can be turned on or off ? 

[FROSTYBALLS]

If they were dealer fit parking sensors, there may be a small on/off switch somewhere on the boot lining - probably near to one of the light clusters.

[Nonsensor]

Nothing I can find, just went through the whole rear section, floor piece out to where the jack etc lives, no evidence of a switch or anything. 

Theres also no bumper warts which I would think are essential in this kind of model year ?